When an electrostatic discharge event occurs to a connection pad of a chip, an electrostatic discharge detector layout in a feedback loop is able to detect an induced electrostatic discharge voltage for generating a control signal. A pass transistor can be turned off by the control signal for isolating the induced electrostatic discharge voltage, and the internal circuit of the chip can be protected from being damaged by the induced electrostatic discharge voltage. Furthermore, the designed circuit based on electrostatic discharge isolation technique for protecting the internal circuit of the chip is compatible with programmable circuits, and the connection pad can be furnished with burning signals or logic signals.